A CHIRAL MESOGENIC COMPOUND

Single-crystal X-ray analysis has been carried out for 4-(1-methylhept yloxycarbonyl)phenyl 4-heptyloxytolanel 4'-carboxylate [C7-tolane, C37 H44O5, tolane = 1,1'-(1,2-ethynediyl)bisbenzene]. The crystal has a sm ectic C-like layer structure composed of largely bent molecules; the c hain of the chiral group is quasi-perpendicular (86 degrees) to the co re moiety. The molecular arrangement is similar to that of 4-[(S)-1-me thylheptyloxycarbonyl]phenyl 4'-octyloxybiphenyl-4-carboxylate and agr ees with the data of the n = 8 homologue (C8-tolane) antiferroelectric mesophase.